Previous research has shown that depressed and anxious people are more likely to have heart attacks and to die from them than those whose dispositions are sunnier. But the Johns Hopkins researchers say their study shows that a general sense of well-being -- feeling cheerful, relaxed, energetic and satisfied with life -- actually reduces the chances of a heart attack.

A report on the research is published in the American Journal of Cardiology.

"If you are by nature a cheerful person and look on the bright side of things, you are more likely to be protected from cardiac events," says study leader Lisa R. Yanek, M.P.H., an assistant professor in the Division of General Internal Medicine at the Johns Hopkins University School of Medicine. "A happier temperament has an actual effect on disease and you may be healthier as a result."

Yanek cautioned that cheerful personalities are likely part of the temperament we are born with, not something we can easily change. While some have suggested it's possible that people lucky enough to have such a trait are also more likely to take better care of themselves and have more energy to do so, Yanek says her research shows that people with higher levels of well-being still had many risk factors for coronary disease but had fewer serious heart events.

She emphasized that the mechanisms behind the protective effect of positive well-being remain unclear. She also noted that her research offers insights into the interactions between mind and body, and could yield clues to those mechanisms in the future.

For the study, Yanek and her colleagues first looked at data from GeneSTAR (Genetic Study of Atherosclerosis Risk), a 25-year Johns Hopkins project sponsored by the National Institutes of Health to determine the roots of heart disease in people with a family history of coronary disease. They analyzed information gathered from 1,483 healthy siblings of people who had coronary events before the age of 60 and who were followed for five to 25 years. Siblings of people with early-onset coronary artery disease (CAD) are twice as likely of developing it themselves.

Among other things, study participants filled out well-being surveys and received a score, on a scale of 0 to 110, which gauged cheerful mood, level of concern about health, whether they were relaxed as opposed to anxious, energy level and life satisfaction. Over the course of an average 12-year follow-up, the researchers documented 208 coronary events -- heart attacks, sudden cardiac death, acute coronary syndrome, and the need for stents or bypass surgery -- in the sibling group.

The researchers found that participants' positive well-being was associated with a one-third reduction in coronary events; among those deemed at the highest risk for a coronary event, there was nearly a 50 percent reduction. The findings took into account other heart disease risk factors such as age, smoking, diabetes, high cholesterol levels and high blood pressure.

To validate their result, the researchers then looked at similar information in a general population using data from 5,992 participants in the first National Health and Nutrition Examination Survey (NHANES). In this population, over an average 16-year follow-up, there were 1,226 coronary events (20.5 percent). They found that this group also benefitted from a cheerful temperament, which reduced their risk of a coronary event by 13 percent.

The findings held whether the participants were white or African-American, men or women.

The research was supported in part by grants from the National Institutes of Health's National Institute of Nursing Research (NR02241), National Heart, Lung, and Blood Institute (R01 HL49762 and R01 HL59684) and National Center for Research Resources (M01 RR00052) to the Johns Hopkins University School of Medicine General Clinical Research Center.

Other Johns Hopkins researchers contributing to this study include Brian G. Kral, M.D., M.P.H.; Taryn F. Moy, M.S.; Dhananjay Vaidya, M.B.B.S., Ph.D., M.P.H.; Mariana Lazo, M.D., Ph.D., Sc.M.; Lewis C. Becker, M.D.; and Diane Becker, Sc.D., M.P.H.